Porous Polymer Network Materials

ABSTRACT

Functionalized Porous Polymer Networks (PPNs) exhibiting favourable characteristics such as high surface area′ and gas uptake properties are disclosed, including methods of making such networks. A method of preparing a porous polymer network, comprising: (a) a step of homo-coupling a monomer in the presence of 2,2′-bipyridyl, 1,5-cycloocta-1,5-diene, a mixed solvent of DMF/THF and a compound or mixture selected from the group consisting of bis(1,5-cydoocta-1,5-diene)nickel(o), Ni(PPH3) 4, and Zn/NiCI2/NaBr/PPH3 at a temperature in the range of 20 to 40° C. These stable PPNs may be useful in the context of carbon capture, gas storage and separation, and as supports for catalysts.

GOVERNMENT RIGHTS

The invention was made with government support under Grant Nos.DE-AR0000073 and DE-FC36-07GO17033 awarded by the Department of Energy.The government has certain rights to the invention.

FIELD OF INVENTION

The present invention relates to porous polymer network materials(PPNs). In particular, the invention relates to porous polymer networkmaterials comprising a functional group, and methods of preparing same.

SUMMARY OF INVENTION

Rising atmospheric CO₂ levels and its impact on global ecosystems havebeen strongly correlated to the combustion of fossil fuels. A number ofpotential solutions for conservation and remediation of the environmentdue to the impacts of CO₂ release are under consideration. These includecarbon capture and sequestration (CCS), a process which separates CO₂from the flue gas of coal-fired power plants and stores the CO₂underground, as well as the utilization of cleaner fuels, such asmethane (CH₄) or hydrogen (H₂).

Current CO₂ capture processes employed in power plants worldwide includepost-combustion ‘wet scrubbing’ methods, which involve chemicaladsorption of CO₂ by amine solutions such as mono-ethanolamine (MEA).This process requires the amine solutions to chemically react with CO₂,forming carbamates, which results in the scrubber having a high capacityand selectivity for CO₂. However, this process exhibits some significantdrawbacks. In particular, a large amount of energy is required toregenerate the system and the amine solutions are highly corrosive, eachof which can pose significant problems during extended operation.

To sidestep the huge energy demand, corrosion problem, and otherlimitations associated with traditional wet scrubbers, researchattention has focussed on the use of solid absorbents as an alternativeapproach. Compared to the conventional scrubbing technique describedabove, in which a large amount of water must be heated and cooled duringthe regeneration of the dissolved amines, it has been found that thesolid absorbent approach improves the energy efficiency of theregeneration process by eliminating the need to heat water.

Furthermore, due to depletion of fossil oil deposits in recent years,clean energy research has also focussed on developing methods toefficiently trap and store gas molecules, such as H₂ and CH₄. While CH₄combustion does still produce CO₂, it is much cleaner burning thanpetroleum-based fuels. The preeminent factor preventing thecommercialization of these fuels is the discovery of effective methodsto reversibly store these energy related gases.

The two common methods of gas storage are liquefaction at lowtemperature and compression at room temperature. These methods areexpensive and pose risks. To overcome these problems, research intoadsorption technologies, where a guest species adheres to the surface ofmaterials, forming a layer of adsorbed molecules, has been proposed.While the use of porous materials in H₂ storage devices is yet be fullyrealized, the storage of methane at relatively low pressure and ambienttemperature in porous sorbents is presently an achievable goal.

Porous materials have been deemed to be viable storage alternatives forgas molecules, such as CO₂ and CH₄, because of their high porosity andtherefore significantly increased accessible contact area with gasmolecules. This enables separation of a selected gas from a mixture ofgases, storage of a selected gas or gases and regeneration of the porousmaterial to be performed under relatively mild conditions compared toamine wet scrubbing systems. In particular, metal-organic frameworks(MOFs), which possess discrete or extended structures in which the poresize and cavities of the materials have been configured for trapping asingle molecule, as described for example in Furukawa et al., Science,2010, 329, 424-428, have been investigated. In addition, porous polymernetworks, which are generated from tetrahedral monomers which whenpolymerized provide a default diamondoid framework topology having wideopenings and interconnected pores with limited ‘dead space’, have alsobeen considered as viable storage alternatives for gas molecules such asCO₂ and CH₄. Unfortunately, only moderate CH₄ and CO₂ uptake capacitieshave been observed in the art under carbon capture conditions. Inaddition, many porous materials suffer from limited stability and highregeneration energy requirements, which hamper their practicalapplication for gas separation and storage.

Accordingly, there is a need for new materials which can obviate ormitigate some of the disadvantages associated with the prior art. Forinstance, it would be beneficial to provide materials which show highselectivity for a particular gas, such as CO₂ or CH₄. It would also beuseful to provide materials which have low regeneration energyrequirements. In addition, it would be advantageous to provide materialswhich have high storage capacities, for gases such as H₂, CH₄ and CO₂.

In a first aspect of the present invention there is provided a porouspolymer network comprising a moiety of Formula (A)

wherein T is —C, —Si, —Ge, —Sn, —P, —B, —N, —C₁₀H₁₆ (adamantane), —NO₂,—CHO, —OH, —OCH₃ or —OCH₂CH₃,

R₁ to R₁₆ are each independently selected from —H, —F, —Cl, —Br, —I,—OH, —NH₂, an alkyl, CH₂Q, COQ and SO₂Q, wherein Q is a functionalgroup, and at least one of R₁ to R₁₆ is CH₂Q, COQ or SO₂Q, with theproviso that when at least one of R₁ to R₁₆ is COQ, Q is not NH₂ andthat when at least one of R₁ to R₁₆ is CH₂Q, Q is not an alkyl group.

In an embodiment of the invention, T is selected from the groupconsisting of —C, —Si, —Ge and —C₁₀H₁₆ (adamantane).

In an embodiment of the invention, T is —Si.

In an embodiment of the invention, T is —C.

In an embodiment of the invention, the functional group is selected froman alkyl group having 1 to 6 carbon atoms, an amine and a polyamine.

In an embodiment of the invention, the functional group is —C₃H₇, —C₄H₉,—C₅H₁₁ or —C₆H₁₃.

In an embodiment of the invention, at least one of R₁ to R₁₆ is CH₂Q.

In an embodiment of the invention, Q is a polyamine.

In an embodiment of the invention, the polyamine is represented by theformula N(A₁)A₂, wherein A₁ and A₂ are each independently selected from—H, a saturated or unsaturated polyalkylamine and a saturated orunsaturated polyalkarylamine, preferably, wherein one or more amineunits in the polyalkylamine or polyalkarylamine is optionally aquaternary ammonium.

In an embodiment of the invention, the polyamine is represented byN(A₁)A₂, wherein A₁ and A₂ are each independently selected from —H, abranched or unbranched alkyl or a branched or unbranched alkylaminehaving 1 to 12 carbon atoms which is optionally mono- or polysubstitutedby —OH or —NH₂, and wherein one or more non-adjacent —CH₂ groups isoptionally replaced, in each case independently from another by —O—, or—N(A₃), wherein A₃ is —H, a branched or unbranched alkyl or a branchedor unbranched alkylamine having 1 to 12 carbon atoms, with the provisothat at least one of A₁ and A₂ is not hydrogen.

Preferably, N(A₁)A₂ is selected from the group consisting of:

More preferably, N(A₁)A₂ is

In an embodiment of the invention, the proportion of amine per gram ofthe porous polymer network is in the range of 1 to 1000 mmol.

In a second aspect of the invention there is provided a method ofpreparing a porous polymer network, comprising:

(a) a step of homo-coupling a monomer of formula 1

in the presence of 2,2′-bipyridyl, 1,5-cycloocta-1,5-diene, a mixedsolvent of DMF/THF and a compound or mixture selected from the groupconsisting of bis(1,5-cycloocta-1,5-diene)nickel(o), Ni(PPH₃)₄, andZn/NiCl₂/NaBr/PPH₃, at a temperature in the range of 20 to 40° C.,

wherein T is —C, —Si, —Ge, —Sn, —P, —B, —N, —C₁₀H₁₆ (adamantane), —NO₂,—CHO, —OH, —OCH₃ or —OCH₂CH₃

R is —F, —Cl, —Br, —I, an alkenyl group or an alkynyl group,

R₁ to R₁₆ are each independently selected from —H, —F, —Cl, —Br, —I,—OH, —NH₂ and an alkyl group; and

(b) a step of functionalizing the product obtained in step (a) with acompound represented by a formula selected from CH₂Q, SO₂Q and COQ,wherein Q is a functional group, with the proviso that when the productobtained in step (a) is functionalized with CH₂Q, Q is not an alkylgroup.

In an embodiment of the invention, T is selected from the groupconsisting of —C, —Si, —Ge and —C₁₀H₁₆ (adamantane).

In an embodiment of the invention, T is —Si.

In an embodiment of the invention, T is —C.

In an embodiment of the invention, the functional group is selected froman alkyl group having 1 to 6 carbon atoms, an amine and a polyamine.

In an embodiment of the invention, the product obtained in step (a) isfunctionalized with CH₂Q. Q may be a polyamine.

In an embodiment of the invention, the product obtained in step (a) isfunctionalized with a compound represented by formula CH₂N(B₁)B₂,CON(B₁)B₂ or SO₂N(B₁)B₂, wherein B₁ and B₂ are each independentlyselected from —H, a saturated or unsaturated polyalkylamine and asaturated or unsaturated polyalkarylamine, preferably, wherein one ormore amine units in the polyalkylamine or polyalkarylamine is optionallya quaternary ammonium.

In an embodiment of the invention, the product obtained in step (a) isfunctionalized with a compound represented by formula CH₂N(B₁)B₂,wherein B₁ and B₂ are each independently selected from —H, a branched orunbranched alkyl or a branched or unbranched alkylamine having 1 to 12carbon atoms which is optionally mono- or polysubstituted by —OH or—NH₂, and wherein one or more non-adjacent —CH₂ groups is optionallyreplaced, in each case independently from another by —O—, or —N(A₃),wherein A₃ is —H, a branched or unbranched alkyl or a branched orunbranched alkylamine group having 1 to 12 carbon atoms, with theproviso that at least one of B₁ and B₂ is not —H.

In an embodiment of the invention, the ratio of THF:DMF used in step (a)is in the range of 1:10 to 10:1. Preferably, the ratio of THF:DMF is inthe range of 1:5 to 5:1. More preferably, the ratio of THF:DMF is 1:1.

In a third aspect of the present invention, there is provided a porouspolymer network obtained or obtainable by a process according to thepresent invention in its second aspect.

In a fourth aspect of the present invention, there is provided a methodof storing a gas comprising a step of incorporating a gas into a porouspolymer network according to the present invention in its first aspector a porous polymer network according to the present invention in itsthird aspect. In an embodiment of the invention, the gas is CH₄.

In a fifth aspect of the present invention, there is provided a methodof separating a gas from a gaseous mixture, comprising a step ofcontacting the gaseous mixture with a porous polymer network accordingto the present invention in its first aspect or a porous polymer networkaccording to the present invention in its third aspect, such that aselected gas is incorporated into the porous polymer network and isthereby separated from the gaseous mixture.

In an embodiment of the present invention, the gaseous mixture comprisesCO₂ and N₂. In an embodiment of the invention, the selected gas is CO₂.

In a sixth aspect of the invention, there is provided a porous polymernetwork comprising a moiety of Formula (A)

wherein T is —C, —Si, —Ge, —Sn, —P, —B, —N, —C₁₀H₁₆, —NO₂, —CHO, —OH,—OCH₃ or —OCH₂CH₃,

R₁ to R₁₆ are each independently selected from —H, —F, —Cl, —Br, —I,—OH, —NH₂ and an alkyl.

In an embodiment of the invention, T is —C, —Si, —Ge and —C₁₀H₁₆.

In an embodiment of the invention, T is —Si.

The PPN may have a Brunauer-Emmett-Teller (BET) surface area of 1000m²/g to 7000 m²/g. The PPN may have a Langmuir surface area of 2000 m²/gto 12,000 m²/g. The PPN may have an H₂ gas uptake range of 2 wt % to 10wt % at 77 K and 70 bar. The PPN may have an N₂ gas uptake range of 500cm³/g to 1500 cm³/g at 77 K and 1 bar. The PPN may have a CO₂ gas uptakerange of 50 cm³/g to 200 cm³/g at 295 K and 1 bar. In an embodiment ofthe invention, the PPN has a total CH₄ gas uptake in the range of 200 to500 mg/g at 55 bar. In an embodiment of the invention, the PPN has atotal CH₄ gas uptake in the range of 250 to 400 mg/g at 55 bar.

In an embodiment of the invention, each of R₁ to R₁₆ is —H.

In a seventh aspect of the invention, there is provided a method ofpreparing a porous polymer network, comprising:

(a) a step of homo-coupling a monomer of formula 1

in the presence of 2,2′-bipyridyl, 1,5-cycloocta-1,5-diene, a mixedsolvent of DMF/THF, and a compound or mixture selected from the groupconsisting of bis(1,5-cycloocta-1,5-diene)nickel(o), Ni(PPH₃)₄, andZn/NiCl₂/NaBr/PPH₃, at a temperature in the range of 20 to 40° C.,

wherein T is —C, —Si, —Ge, —Sn, —P, —B, —N, —C₁₀H₁₆ (adamantane), —NO₂,—CHO, —OH, —OCH₃ or —OCH₂CH₃,

R is —F, —Cl, —Br, —I, an alkenyl group or an alkynyl group,

R₁ to R₁₆ are each independently selected from —H, —F, —Cl, —Br, —I,—OH, —NH₂ and an alkyl group.

In an embodiment of the invention, T is —Si.

In an embodiment of the invention, critical point drying is used toremove the solvent.

In an eighth aspect of the present invention, there is provided a porouspolymer network obtained or obtainable by a process according to thepresent invention in its seventh aspect.

The porous polymer network produced according to the present inventionin its seventh aspect may have a Brunauer-Emmett-Teller (BET) surfacearea of 1000 m²/g to 7000 m²/g. The PPN may have a Langmuir surface areaof 2000 m²/g to 12,000 m²/g. The PPN may have an H₂ gas uptake range of2 wt % to 10 wt % at 77 K and 70 bar. The PPN may have an N₂ has uptakerange of 500 cm³/g to 1500 cm³/g at 77 K and 1 bar. The PPN may have aCO₂ gas uptake range of 50 cm³/g to 200 cm³/g at 295 K and 1 bar. In anembodiment, the PPN has a CH₄ gas uptake in the range of 200 to 500 mg/gat 55 bar. In an embodiment of the invention, the PPN has a total CH₄gas uptake in the range of 250 to 400 mg/g at 55 bar.

In a ninth aspect of the invention, there is provided a method ofstoring a gas comprising incorporating a gas into a porous polymernetwork according to the present invention in its sixth aspect or aporous polymer network according to the present invention in its eighthaspect. The gas may be CH₄.

In a tenth aspect of the invention, there is provided a method ofseparating a gas from a gaseous mixture, comprising a step of contactingthe gaseous mixture with a porous polymer network according to thepresent invention in its sixth aspect or a porous polymer networkaccording to the present invention in its eighth aspect, such that aselected gas is incorporated into the porous polymer network and isthereby separated from the gaseous mixture. In an embodiment of theinvention, the gaseous mixture comprises CO₂ and N₂. In an embodiment ofthe invention, the selected gas is CO₂.

Embodiments of the invention will now be described, by way of exampleonly, with reference to the accompanying drawings, in which:

FIG. 1 illustrates a synthetic scheme for post-synthetic introduction ofpolyamine groups into PPN-6, according to an embodiment of theinvention.

FIG. 2 illustrates pore size distribution curves of PPN-6-CH₂Cl andPPN-6-CH₂DETA (DETA=diethylenetriamine), according to an embodiment ofthe invention.

FIG. 3 shows a N₂ sorption isotherm collected at 77 K for materialsPPN-6-CH₂Cl, PPN-6-CH₂DETA, PPN-6-CH₂TAEA(TAEA=tris(2-aminoethyl)amine), PPN-6-CH₂TETA(TETA=triethylenetetramine), PPN-6-CH₂EDA (EDA=ethylenediamine),according to an embodiment of the invention.

FIG. 4 shows a N₂ sorption isotherm collected at 295 K for materialsPPN-6-CH₂Cl, PPN-6-CH₂EDA and PPN-6-CH₂DETA, according to an embodimentof the invention.

FIG. 5 shows a CO₂ sorption isotherm collected at 295 K for materialsPPN-6-CH₂Cl, PPN-6-CH₂DETA, PPN-6-CH₂TAEA, PPN-6-CH₂TETA andPPN-6-CH₂EDA, according to an embodiment of the invention.

FIG. 6 illustrates LAST calculated component loadings of N₂ and CO₂ withbulk gas phase partial pressures of 85 kPa and 15 kPa for N₂ and CO₂,respectively, for materials PPN-6-CH₂Cl, PPN-6-CH₂DETA, PPN-6-CH₂EDA,PPN-6-SO₃Li, NaX zeolite, MgMOF-74 and mmen-CuBTTri, according to anembodiment of the invention.

FIG. 7 illustrates the results of a regeneration evaluation performed onPPN-6-CH₂DETA, according to an embodiment of the invention.

The porous polymer network according to the present invention comprisesa moiety of Formula (A)

wherein T is —C, —Si, —Ge, —Sn, —P, —B, —N, —C₁₀H₁₆ (adamantane), —NO₂,—CHO, —OH, —OCH₃ or —OCH₂CH₃,

R₁ to R₁₆ are each independently selected from —H, —F, —Cl, —Br, —I,—OH, —NH₂, an alkyl, CH₂Q, COQ and SO₂Q, wherein Q is a functionalgroup, and at least one of R₁ to R₁₆ is CH₂Q, COQ or SO₂Q, with theproviso that when at least one of R₁ to R₁₆ is COQ, Q is not NH₂ andthat when at least one of R₁ to R₁₆ is CH₂Q, Q is not an alkyl group.

A porous polymer network is a porous network of covalently bondedmoieties which are cross-linked to form a three-dimensional structure. Aporous polymer network may be a porous network of covalently bondedmoieties of formula (a). The PPNs according to the present inventiontypically have diamondoid structures and ultra-high surface areas thatexceed those of presently known PPNs. In addition, carbon-carbon bondsinterconnecting the network also serve to impart thermal and chemicalstability such that post-synthetic treatments are tolerated. In someembodiments, a PPN exhibits a BET (Brunauer-Emmett-Teller) surface areain the range of 1000 m²/g to 7000 m²/g or more.

As described herein, the term ‘functional group’ refers to an atom or agroup of atoms that has similar chemical properties whenever it occursin different compounds. In some embodiments, the functional group is analkyl, alkenyl, alkynyl, an amine or a polyamine.

As used herein, ‘alkyl’ refers to a straight-chain alkyl, abranched-chain alkyl, a cycloalkyl (alicyclic), or a cyclic alkyl. Thealkyl groups may have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, or morecarbon atoms, or any range derivable therein. In some embodiments, thealkyl group has 1-6 carbon atoms, i.e. 1, 2, 3, 4, 5, or 6 carbon atoms.The groups —CH₃, —CH₂CH₃, —CH₂CH₂CH₃, —CH(CH₃)₂, —CH(CH₂)₂,—CH₂CH₂CH₂CH₃, —CH(CH₃)CH₂CH₃, —CH₂CH(CH₃)₂, —C(CH₃)₃, —CH₂C(CH₃)₃,cyclobutyl, cyclopentyl and cyclohexyl, are all non-limiting examples ofalkyl groups.

According to the present invention, the term ‘amine’ refers to acompound derived from ammonia by replacing one, two or three hydrogenatoms by a hydrocarbyl group. As described herein, the term ‘polyamine’refers to an organic compound having two or more amine groups, whereineach amine group may be a primary amine, a secondary amine or a tertiaryamine.

The present inventors have found that by tethering an amine or apolyamine to a porous polymer network of the present invention, forinstance as in synthesis example 1.1.3, the PPN exhibits stronger CO₂adsorption interactions than conventional PPNs and therefore has muchhigher CO₂ adsorption capacity at low pressure. In addition, it has beenfound that strong interactions between the surface of the PPN and CO₂are formed when the PPN is tethered with an amine or polyamine. Thisresults in high CO₂/N₂ adsorption selectivities under ambientconditions. Furthermore, it has been found that polyamine-tethered PPNsexhibit substantially lower regeneration energies than traditional aminescrubber solutions, in which the higher chemisorption interaction (˜50to 100 kJ/mol) necessitates heating the solutions, which contain about70% water, to around 100° C. As detailed in the results section,polyamine-tethered PPNs are particularly advantageous as they have beenfound to show unprecedented CO₂ removal from systems of high and lowconcentrations of CO₂. In particular, polyamine-tethered PPNs show highthermal and chemical stability (higher even than for amine-tetheredPPNs), especially when considering the sensitivity of the material towater and air.

In an embodiment of the invention, T is selected from the groupconsisting of C₁₀H₁₆ (adamantane) (PPN-3), Si (PPN-4), Ge (PPN-5) and C(PPN-6). Preferably, T is Si. PPN-4 exhibits superior stability, whencompared with conventional porous materials, and therefore it is a verypromising candidate for gas storage applications. The exceptionally highstorage capacities of PPN-4 combined with excellent stability make PPN-4a very attractive candidate for gas storage applications, particularlyfor the storage of H₂, CH₄ and CO₂.

In an embodiment of the invention, T is C. Purely organic porous polymernetworks are advantageous as they exhibit surface area comparable toconventional MOFs (metal-organic frameworks), but have much higherphysicochemical stability due to the entirely covalently bonded network.

In an embodiment of the invention, the functional group is selected froman alkyl group having 1 to 6 carbon atoms, an amine and a polyamine. Thefunctional group may be —C₃H₇, —C₄H₉, —C₅H₁₁ or —C₆H₁₃.

In an embodiment of the invention, the at least one of R₁ to R₁₆ isCH₂Q.

In an embodiment of the invention, Q is a polyamine.

In an embodiment of the invention, the polyamine is represented byN(A₁)A₂, wherein A₁ and A₂ are each independently selected from —H, asaturated or unsaturated polyalkylamine and a saturated or unsaturatedpolyalkarylamine.

The polyalkarylamine may be

In an embodiment of the invention, one or more amine units in thepolyalkylamine or polyalkarylamine is a quaternary ammonium.

In an embodiment of the invention, the polyamine is represented byN(A₁)A₂, wherein A₁ and A₂ are each independently selected from —H, abranched or unbranched alkyl or a branched or unbranched alkylaminehaving 1 to 12 carbon atoms which is optionally mono- or polysubstitutedby —OH or —NH₂, and wherein one or more non-adjacent —CH₂ groups isoptionally replaced, in each case independently from another by —O—, or—N(A₃), wherein A₃ is —H, a branched or unbranched alkyl or a branchedor unbranched alkylamine having 1 to 12 carbon atoms, with the provisothat at least one of A₁ and A₂ is not hydrogen.

Preferably, N(A₁)A₂ is selected from the group consisting of:

More preferably, N(A₁)A₂ is

The adsorption selectivity of CO₂ over other gases, such as N₂, has beenevaluated for polyamine-tethered PPN-6 (wherein T in Formula (A) is C).As explained in detail below, the present inventors found thatpolyamine-tethered PPN-6 strongly interacts with CO₂ over a wide rangeof pressures and temperatures.

In an embodiment of the invention, the proportion of amine per gram ofthe porous polymer network is in the range of 1 to 1000 mmol. Theproportion of amine per gram of the porous polymer network may be in therange of 1 to 200 mmol/g. Preferably, the proportion of amine per gramof the porous polymer network is in the range of 1 to 10 mmol/g.

The method for preparing a porous polymer network according to thepresent invention comprises:

(a) a step of homo-coupling a monomer of formula 1

in the presence of 2,2′-bipyridyl, 1,5-cycloocta-1,5-diene, a mixedsolvent of DMF/THF and a compound or mixture selected from the groupconsisting of bis(1,5-cycloocta-1,5-diene)nickel(o), Ni(PPH₃)₄ andZn/NiCl₂/NaBr/PPH₃, at a temperature in the range of 20 to 40° C.,

wherein T is C, Si, Ge, Sn, P, B, N, C₁₀H₁₆ (adamantane), NO₂, CHO, OH,OCH₃ or OCH₂CH₃,

R is —F, —Cl, —Br, —I, an alkenyl group or an alkynyl group,

R₁ to R₁₆ are each independently selected from —H, —F, —Cl, —Br, —I,—OH, —NH₂ and an alkyl group; and

(b) a step of functionalizing the product obtained in step (a) with acompound selected from CH₂Q, SO₂Q and COQ, wherein Q is a functionalgroup, with the proviso that when the product obtained in step (a) isfunctionalized with COQ, Q is not NH₂ and that when the product obtainedin step (a) is functionalized with CH₂Q, Q is not an alkyl group.

As described herein, the term ‘alkenyl’ may include straight-chainalkenyl, branched-chain alkenyl, cycloalkenyl and cyclic alkenyl.Alkenyl groups may comprise 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, ormore carbon atoms, or any range derivable therein. For example, thealkenyl group may have 1 to 6 carbon atoms. In particular, the alkenylgroup may be —CH₂═CH₂, —CH═CHCH₃, —CH═CHCH₂CH₃, —CH₂CH═CH₂ or—H₂CH═CHCH₃.

As described herein, the term ‘alkynyl’ may include straight-chainalkynyl, branched-chain alkynyl, cycloalkynyl, and cyclic alkynyl.Alkynyl groups may comprise 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, ormore carbon atoms, or nay range derivable therein. For example, thealkynyl group may have 1 to 6 carbon atoms. In particular, the alkynylgroups may be —C≡CH or —C≡CCH₃.

The monomer of formula 1 is homocoupled under modified Yamamoto couplingconditions. Yamamoto coupling conditions are known in the art and referto coupling of terminal halogens using bis(1,5-cyclooctagiene)nickel(o),DMF, 2,2′-bipyridyl, and 1,5-cyclooctadiene in the presence of elevatedtemperatures (e.g., 80 C). See, e.g., Holst et al., Macromolecules43:8531 (201); Schmidt et al., Macromolecules, 42:4426 (2009); and Benet al., Angew. Chemie Int. Ed. 48:9457 (2009). Modified Yamamotocoupling conditions refer to Yamamoto coupling conditions as describedabove but that take place in a mixture of DMF and THF at roomtemperature.

Preparation of the PPNs using the optimized Yamamoto coupling conditionsdescribed herein, helps eliminate unreacted termini of the monomerstarting materials and facilitates formation of highly connectedframeworks.

In an embodiment of the present invention, the monomer of formula 1 ishomo-coupled in the presence of 2,2′-bipyridyl, 1,5-cycloocta-1,5-diene,a mixed solvent of DMF/THF and bis(1,5-cycloocta-1,5-diene)nickel(0), ata temperature in the range of 20 to 40° C.

The inventors have found that the modified Yamamoto coupling conditionsdiscussed above result in a PPN with significantly higher BET surfacearea than the surface area of a PPN produced using conventional couplingconditions, such as standard Yamamoto coupling conditions. Inparticular, the inventors have found that PPNs prepared using themodified coupling conditions may have one or more characteristics asfollows. The PPNs may have a Brunauer-Emmett-Teller (BET) surface areaof about moo m²/g to about 7000 m²/g. The PPNs may have a Langmuirsurface area of about 2000 m²/g to about 12,000 m²/g. The PPNs may havean H₂ gas uptake range of about 2 wt % to about 10 wt % at about 77 Kand about 70 bar. The PPNs may have an N₂ gas uptake range of about 500cm³/g to about 2500 cm³/g at about 77 K and about 1 bar and the PPNs mayhave a CO₂ gas uptake range of about 50 cm³/g to about 200 cm³/g atabout 295 K and about 1 bar.

The PPNs typically feature surface areas or gas uptakes that exceedthose of presently known PPNs. In some embodiments, a PPN exhibits a BETsurface area in the range of moo to 8000 m²/g, or a BET surface area of,at least, or at most 1000, 1250, 1750, 2000, 2250, 2500, 2750, 3000,3250, 3500, 3750, 4000, 4250, 4500, 4750, 5000, 5350, 5500, 5750, 6000,6100, 6200, 6250, 6300, 6400, 6500, 6600, 6700, 6750, 6800, 6900, 7000,7100, 7200, 7250, 7300, 7400, 7500, 7600, 7700, 7750, 7800, 7900, or8000 m²/g, or more, or any range derivable therein. In some embodiments,a PPN exhibits a Langmuir surface area in the range of 45000 m²/g to13000 m²/g, or a Langmuir surface area of, at least, or at most 2000,2250, 2500, 2750, 3000, 3250, 3500, 3750, 4000, 4250, 4500, 4750, 5000,5250, 5500, 5750, 6000, 6100, 6200, 6250, 6300, 6400, 6500, 6600, 6700,6750, 7000, 7250, 7750, 8000, 8250, 8500, 9000, 9250, 9500, 9750, 10000,10250, 10500, 10750, 11000, 11250, 11500, 11750, 12000, 12250, 12500,12750, or 13000 m²/g, or more, or any range derivable therein. In someembodiments, H₂ uptake is in the range of 4 to 10 wt %, or the H₂ uptakeis at least, or at most 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or15% or more, or any range derivable therein, at about 77 K and about 70bar. In some embodiments, N₂ uptake is in the range of 500-3500 cm³/g orthe N₂ uptake is at least, or at most 500, 750, 1000, 1250, 1500, 1750,2000, 2250, 2500, 3000 or 3500 cm³/g, or any range derivable therein, atabout 77 K and about 1 bar. In some embodiments, CO₂ uptake is in therange of 100 to 200 cm³/g or the CO₂ uptake is at least, or at most 50,75, 100, 125, 150, 175 or 200 cm³/g or more, or any range derivabletherein, at about 295 K and about 1 bar. One or more of each of theseproperties may be exhibited by a single PPN.

In an embodiment of the invention, the ratio of DMF:THF is in the rangeof 1:10 to 10:1. Preferably, the ratio of DMF:THF is in the range of 1:5to 5:1. More preferably, the ratio of DMF:THF is 1:1. It has beendetermined that the ratio of DMF:THF has a beneficial effect on the BETsurface area of the resulting PPN, as demonstrated in the resultssection below.

In an embodiment of the invention, T is selected from the groupconsisting of C, Si, Ge and C₁₀H₁₆ (adamantane). Preferably, T is C. Inan embodiment of the invention, T is Si.

In an embodiment of the invention, the functional group is selected froman alkyl group having 1 to 6 carbon atoms, an amine and a polyamine.

In an embodiment of the invention, the product obtained in step (a) isfunctionalized with CH₂Q. Q may be a polyamine.

In an embodiment of the invention, the product obtained in step (a) isfunctionalized with a polyamine group. As detailed in the resultssection, polyamine-tethered PPNs, which can be produced according to themethod described above, are particularly advantageous as they have beenfound to show unprecedented CO₂ removal from systems of high and lowconcentrations of CO₂ The inventors have found that polyamine-tetheredPPNs have extremely high CO₂ capacity at very low pressures because ofthe multiple adsorption sites, which is desired for CO₂ capture fromflue gas or air. In addition, polyamine-tethered PPNs show high thermaland chemical stability (higher even than for amine-tethered PPNs),especially when considering the sensitivity of the material to water andair.

According to an embodiment of the present invention the PPN isfunctionalized with a polyamine group. The polyamine may be representedby formula N(B₁)B₂, wherein B₁ and B₂ are each independently selectedfrom —H, a saturated or unsaturated polyalkylamine, a saturated orunsaturated polyarylamine and a saturated or unsaturatedpolyalkarylamine.

The polyalkarylamine may be

In an embodiment of the second aspect of the invention, the polyamine isrepresented by formula N(B₁)B₂, wherein B₁ and B₂ are each independentlyselected from —H, a branched or unbranched alkyl or a branched orunbranched alkylamine having 1 to 12 carbon atoms which is optionallymono- or polysubstituted by —OH or —NH₂, and wherein one or morenon-adjacent —CH₂ groups is optionally replaced, in each caseindependently from another by —O—, or —N(A₃), wherein A₃ is —H, abranched or unbranched alkyl or a branched or unbranched alkylaminehaving 1 to 12 carbon atoms, with the proviso that at least one of B₁and B₂ is not hydrogen.

Preferably, the polyamine is selected from

More preferably, the polyamine is

In the present invention, the functional group or amine or polyamine isattached to the PPN via a linker molecule. The linker molecule may beCO, CH₂ or SO₂. The PPN may be functionalized by a two or more stepprocess. The first step may involve introducing a linker molecule intothe PPN and the second step may involve reacting the product of thefirst step with a functional group or an amine or polyamine. In anembodiment of the invention, the PPN is functionalised by a first stepin which a —CHO group, a compound of formula CH₂X, a compound of formulaCOX, or a compound of formula SO₂X is introduced into the PPN, wherein Xis selected from —Cl, F, Br and —I and a second step in which theproduct of the first step is reacted with a functional group or an amineor polyamine.

In an embodiment of the invention, the product of the first step isreacted with a polyamine.

In an embodiment of the invention, the polyamine is selected from

An aspect of the present invention, there is provided a porous polymernetwork obtained or obtainable by a process according to the presentinvention in its second aspect.

PPNs as disclosed herein may be used, for example, in the context ofcarbon capture, gas storage and separation (e.g. separation of a mixtureof gases), or supports for catalysts or other chemicals. Other usesinclude liquid sorption, size-selective separation of nanoparticles,immobilization of nanoparticles, preparation of a sensor device,controlled release of a substance from the network, and as anelectrically conducting component in a device. An aspect of the presentinvention provides a method of storing a gas comprising incorporating agas into a porous polymer network as described herein. The gasincorporated into the porous polymer network may be CH₄. In anembodiment of the invention, a gas of choice may be selectively storedin comparison to a second gas. The gas of choice may be CO₂. The secondgas may be N₂.

An aspect of the invention provides a method of separating a gas from agaseous mixture, comprising a step of contacting the gaseous mixturewith a porous polymer network as described herein, such that a selectedgas is incorporated into the porous polymer network and is therebyseparated from the gaseous mixture. The gaseous mixture may comprise CO₂and N₂. The selected gas may be CO₂.

The invention will now be described by way of illustration only on thefollowing examples.

1. Preparation of PPNs SYNTHESIS EXAMPLE 1.1 Preparation of PPN-6

All reagents and chemicals were purchased from Aldrich, Alfa, and Acros.N,N-Dimethylformamide (DMF) and Tetrahydrofuran (THF) were degassedbefore use. Tetrakis(4-bromophenyl)methane was synthesized as describedin Chem. Mater., 2010, 22, 5964-5972.

To a solution of 2,2′-bipyridyl (226 mg, 1.45 mmol),bis(1,5-cyclooctadiene)nickel(o) (Ni(COD)₂, 400 mg, 1.45 mmol), and1,5-cyclooctadiene (COD, 0.18 mL, 1.46 mmol) in anhydrous DMF/THF (30mL/30 mL), tetrakis(4-bromophenyl)methane (205 mg, 0.32 mmol) was added,and the mixture was stirred at 25° C. under an argon gas atmosphere for10 hours. Then, the mixture was cooled in an ice bath, 6 mol/L HClsolution (20 mL) was added and the resulting mixture was stirred foranother 6 hours. The precipitate was collected, washed with methanol(6×10 mL) and H₂O (6×10 mL), respectively, and dried in vacuo at 120° C.for 10 hours to produce PPN-6 as an off-white powder (85 mg, 85%).

Elemental analysis calc. (%) for C₂₅H₁₆: C, 94.94; H, 5.06. found: C,93.51; H, 5.25; Solid-state ¹³C NMR (4 mm, Bybass, 10 KHz, Field=−2000,p15=2000): 142.6, 136.2, 127.8, 122.0.

SYNTHESIS EXAMPLE 1.2 Preparation of PPN-3

PPN-3 was synthesised in the same manner as PPN-6 of synthesis example1.1, except that tetrakis(4-bromophenyl)adamantane was used instead oftetrakis(4-bromophenyl)methane.

Elemental analysis calc. (%): C, 96.54; H, 6.46; N, 0.0; Br, 0.0. found:C, 90.44; H, 6.57; N, 0.11; Br, 0.00.

SYNTHESIS EXAMPLE 1.3 Preparation of PPN-4

PPN-4 was synthesised in the same manner as PPN-6 of synthesis example1.1, except that tetrakis(4-bromophenyl)silane was used instead oftetrakis(4-bromophenyl)methane.

Elemental analysis calc. (%): C, 86.70; H, 4.85. found: C, 84.35; H,4.93.

SYNTHESIS EXAMPLE 1.4 Preparation of PPN-5

PPN-5 was synthesised in the same manner as PPN-6 of synthesis example1.1, except that tetrakis(4-bromophenyl)germane was used instead oftetrakis(4-bromophenyl)methane.

Elemental analysis calc. (%): C, 76.46; H, 4.28; N, 0.0: Br, 0.0. found:C, 75.12; H, 4.42; N, 0.14; Br, 0.0.

COMPARATIVE SYNTHESIS EXAMPLE 1.1 Preparation of PAF-1

PAF-1 was synthesized using Yamamoto coupling conditions, as describedin Ben et al., Angew. Chemie. Int. Ed. 48:9457 (2009).

1.1 Evaluation of the Surface Area for PPNs 3-5

The surface area was evaluated for each of PPNs 3 to 5 prepared usingthe modified Yamamoto homo-coupling procedure. The results are shown inTable 1 below.

TABLE 1: Evaluation of the surface area for PPNs 3-5 Material A_(BET)(m²/g) A_(Lang) (m²/g) A_(Calc)* (m²/g) V_(p) (cm³/g) PPN-3 4221 52636940 2.67 PPN-4 6461 10063 6530 3.04 PPN-5 4267 6764 5881 2.60 PAF-15600 7100 6173 3.05 *The accessible surface area was calculated from asimple Monte Carlo integration technique where the probe molecule is‘rolled’ over the framework surface (Frost et al., J. Phys. Chem. B 110:9565 (2006).

The results show that PPN-3, PPN-4, and PPN-5 can be synthesized withexceptionally high surface areas using the modified Yamamoto couplingprocedure.

The surface area of PPN-3, synthesized through this procedure is muchhigher than the value previously reported, and the surface area of PPN-4is close to the value predicted based on the molecular model, indicatingthe excellence of this optimized procedure. With a BET surface area of6461 m²/g and a Langmuir surface area of 10063 m²/g, PPN-4 appears topossess the highest surface area among all the reported porous materialsso far making it a strong candidate for potential applications in gasseparation and storage. In addition, most of the pores in PPN-4 are inthe microporous or microporous/mesoporous region of the PPN, which isbeneficial for gas storage applications.

SYNTHESIS EXAMPLE 1.1.1 Evaluating the Effect the Ratio of DMF:THF Usedin Synthesis Example 1.1 has on the BET Surface Area of the ResultingPPN

PPN-6 was prepared in the same manner as in the method of SynthesisExample 1.1, except that the amount of DMF/THF was varied within therange of 40 mL/20 mL to 20 mL/40 mL. The BET surface area of theresulting PPN-6 materials was then measured.

The results are shown in Table 2 below. For comparison the BET surfacearea of PAF-1 is also shown in Table 2.

TABLE 2 A comparison of the BET surface area for PPN-6 when the ratio ofDMF:THF used in synthesis example 1.1 is altered. BET surface areaReaction condition (m²/g) of PPN-6 DMF (30 mL), 80° C., 1 h (PAF-1condition) 3200 DMF/THF (40 mL/20 mL), 25° C., 10 h 3300 DMF/THF (20mL/40 mL), 25° C., 10 h 3600 DMF/THF (36 mL/24 mL), 25° C., 10 h 3800DMF/THF (24 mL/36 mL), 25° C., 10 h 3600 DMF/THF (30 mL/30 mL), 25° C.,10 h 4100

It is clear from Table 2 that the BET surface area of a PPN is affectedby altering the ratio of DMF to THF used in its synthesis.

2. Gas Sorption Measurements for PPN-4

2.1 Low-Pressure Gas Sorption Measurements

Low pressure (<800 torr) gas sorption isotherms were measured using aMicrometrics ASAP 2020 surface area and pore size analyzer. Prior to themeasurements, the samples were degassed for 10 h at 80° C. UHP gradegases were used for all measurements. Oil-free vacuum pumps and oil-freepressure regulators were used for all measurements to preventcontamination of the samples during the degassing process and isothermmeasurement.

2.2. High-Pressure Gas Sorption Measurements

High pressure excess adsorption of H₂, CH₄ and CO₂ were measured usingan automated controlled Sieverts' apparatus (PCT-Pro 2000 from Setaram)at 77 K (liquid nitrogen bath) or 295 K (room temperature). About 200 mgof PPN-4 was loaded into the sample holder. Prior to the measurements,sample was degassed at 80° C. overnight. The free volume was determinedby the expansion of low-pressure He (<5 bar) at room temperature. Thetemperature gradient between gas reservoir and sample holder wascorrected by applying a correction factor to the raw data, which wasobtained by replacing the sample with a polished stainless steel rod andmeasuring the adsorption isotherm at the same temperature over therequisite pressure regime.

To evaluate its gas storage capacity, high-pressure excess adsorption ofH₂, CH₄ and CO₂ within PPN-4 were measured at 77 K or 295 K. The resultsare shown in Table 3 below.

TABLE 3 A comparison of H₂, CO₂ and CH₄ uptake values for PPN⁻⁴ andPAF⁻¹. Excess Total Excess Total Excess Total H₂ H₂ CO₂ CO₂ CH₄ CH₄uptake uptake uptake uptake uptake uptake Material (mg g⁻¹) (mg g⁻¹) (mgg⁻¹) (mg g⁻¹) (mg g⁻¹) (mg g⁻¹) PPN⁻⁴ 91 158 1710 2121 269 389 (55 bar)(80 bar) (50 bar) (55 bar) (55 bar) (55 bar) PAF⁻¹ 75.3 120 1300 1585(48 bar) (48 bar) (40 bar) (40 bar)

An exceptionally high surface area combined with excellent stabilitymake PPN-4 an attractive candidate for gas storage applications,particularly for the storage of gas molecules such as H₂, CH₄ and CO₂.

3. Amine Tethering SYNTHESIS EXAMPLE 3.1 Preparation of PPN-6-CH₂Cl

A resealable flask was charged with PPN-6 (200 mg), paraformaldehyde(1.0 g), glacial AcOH (6.0 mL), H₃PO₄ (3.0 mL), and conc. HCl (20 mL).The flask was sealed and heated to 90° C. for 3 days. The resultingsolid was collected, washed with water and methanol, and then dried invacuo to produce PPN-6-CH₂Cl as a brown powder in quantitative yield.

SYNTHESIS EXAMPLE 3.2 Preparation of a Polyamine-Tethered PPN (with theSynthesis of PPN-6-CH₂DETA as an Example)

A resealable flask was charged with PPN-6-CH₂Cl (200 mg) anddiethylenetriamine (DETA, 20 mL). The flask was sealed and heated to 90°C. for 3 days. The resulting solid was collected, washed with water andmethanol, and then dried in vacuo to produce PPN-6-CH₂DETA as a brownpowder in quantitative yield.

FIG. 1 shows a scheme for introducing a polyamine group into PPN-6, suchas in Synthesis Example 1.1.3.

3.1 Evaluation of the Efficiency of the Polyamine Tethering

The efficiency of the amine substitution was confirmed by elementalanalysis. For each amine-tethered PPN (PPN-6-CH₂EDA, PPN-6-CH₂TAEA,PPN-6-CH₂TETA, PPN-6-CH₂DETA), the compound was dried at 100° C. undervacuum for 10 hours before elemental analysis measurements were taken.

Results of the elemental analysis are shown in Table 4 below. Forcomparison, elemental analysis was also performed on PPN-6-CH₂Cl, theresults of which are also shown in Table 4.

TABLE 4 Elemental analysis performed on polyamine-tethered PPNs andPPN-6-CH₂Cl PPN-6- PPN-6- PPN-6- PPN-6- PPN-6- CH₂Cl CH₂EDA CH₂TAEACH₂TETA CH₂DETA Cl %* 14.42 0.33 <0.25 <0.25 <0.25 N %* 0.0 7.53 9.319.04 11.95 *Average of 2 measurements

From this data it is evident that the chlorine content of 14.42% inPPN-6-CH₂Cl was reduced to only trace amounts in the polyamine-tetheredPPNs. In addition, these data illustrate that PPN-6-CH₂DETA had thehighest nitrogen content of 11.95%, corresponding to a loading of 0.3functional groups per phenyl ring.

4. Pore Size Evaluation

Pore size distribution data for PPN-6-CH₂Cl and PPN-6-CH₂-DETA werecalculated from the N₂ sorption isotherms based on the DFT model in theMicromeritics ASAP 2020 software package (assuming slit pore geometry).

A comparison of the pore size distribution curves for PPN-6-CH₂Cl andPPN-6-CH₂DETA is shown in FIG. 2.

As illustrated in FIG. 2, the pore sizes of PPN-6-CH₂DETA have narrowedafter amine tethering, which supports that the amination reactionoccurred within the cavities of PPN-6.

5. Creation of PPN Models

The theoretical non-interpenetrated networks of the PPNs describedherein were created by repeating the unit of the monomer molecule andtheir geometrical structures were optimized using the Forcite Plusmodule and the Universal force field in Material Studio 5.5 fromAccelrys (Accelrys, Materials Studio Release Notes, Release 5.5,Accelrys Software, Inc.: San Diego, 2010).

6. Evaluation of the Nitrogen Adsorption Characteristics ofAmine-Tethered PPNs

Nitrogen gas adsorption/desorption isotherms were collected at 77 K forPPN-6-CH₂—Cl, PPN-6-CH₂EDA, PPN-6-CH₂TAEA, PPN-6-CH₂TETA andPPN-6-CH₂DETA. The results are shown in FIG. 3.

It is evident from FIG. 3 that amine-tethered PPNs adsorb less N₂ at 77Kthan PPN-6-CH₂Cl.

Nitrogen gas adsorption/desorption isotherms were also collected at 295K for PPN-6-CH₂—Cl, PPN-6-CH₂EDA and PPN-6-CH₂DETA. The results areshown in FIG. 4.

As illustrated in FIG. 4, at 295 K, polyamine-tethered PPNs adsorb lessN₂ than PPN-6-CH₂Cl. PPN-6-CH₂DETA is especially interesting with anuptake of less than 0.1 wt % N₂ at 1.0 bar, one third of that ofPPN-6-CH₂Cl. It is possible that the added polar sites may enhance N₂adsorption, but this is totally offset by the significant loss insurface area.

7. Evaluation of the CO₂ Adsorption Characteristics of Amine-TetheredPPNs

CO₂ sorption isotherms were collected at 295 K for PPN-6-CH₂—Cl,PPN-6-CH₂EDA, PPN-6-CH₂TAEA, PPN-6-CH₂TETA and PPN-6-CH₂DETA. Theresults are shown in FIG. 5.

It is evident from FIG. 5 that polyamine-tethered PPN-6 shows excellentCO₂ adsorption characteristics at 295 K and at low pressures.Furthermore, FIG. 5 shows that although PPN-6-CH₂DETA has the lowestsurface area, it exhibits the highest CO₂ uptake capacity among all ofthe polyamine-tethered PPNs. This indicates that the CO₂-uptake capacityis closely correlated to amine loading instead of surface area underthese conditions. For example, at 295 K and 1 bar, PPN-6-CH₂DETAexhibits exceptionally high CO₂ uptake (4.3 mmol g⁻¹, 15.8 wt %). Thisvalue is higher than top-performing N-containing microporous organicpolymers such as N-TC-EMC (4.0 mmol g⁻¹), BILP-4 (3.6 mmol g⁻¹) andMFB-600 (2.25 mmol g⁻¹.

Coal fired power plants emit flue gas that contains ˜15% CO₂ at totalpressures around 1 bar, thus CO₂-uptake capacity at ca. 0.15 bar(partial pressure of CO₂ in flue gas) is more relevant to realisticpost-combustion applications. At 295 K and 0.15 bar, PPN-6-CH₂Cl onlytakes up 0.25 mmol g⁻¹ (1.1 wt %), whereas PPN-6-CH₂DETA takes up 3.0mmol g⁻¹ of CO₂ (11.8 wt %). This value is comparable to othertop-performing materials, such as mmen-CuBTTri (9.5 wt % at 298 K), andMgMOF-74 (22.0 wt % at 293 K), while PPN-CH₂DETA stands out with respectto physiocochemical stability due to the covalent bonding in frameworkconstruction. The surge in volumetric uptake capacity withpolyamine-tethering is even more significant from 1.3 g L⁻¹ forPPN-6-CH₂Cl to 37.5 g L⁻¹ for PPN-6-CH₂DETA at 295 K and 1.15 bar (thetap densities were measured to be 0.12 and 0.28 g cm³ for PPN-6-CH₂CLand PPN-6-CH₂DETA respectively).

8. Evaluation of Selective Adsorption

The ideal adsorption solution theory (LAST) model of Myers and Prausnitzwas used to evaluate the effectiveness of the polyamine-tethered PPNsfor CO₂/N₂ separation. The adsorption selectivities of PPN-6-CH₂—Cl,PPN-6-CH₂EDA, PPN-6-CH₂DETA, PPN-6-SO₃Li, NaX zeolite, MgMOF-74 andmmen-CuBTTri for CO₂ over N₂ in flue-gas streams (typically 15% CO₂ and85% N₂) were determined. These values were estimated from experimentalsingle-component isotherms. FIG. 6 shows the LAST calculated componentloadings for each of these compounds.

The inventors have determined that there are two factors for determiningwhether a material will be efficient for CO₂ separation, i) high CO₂loading and ii) high selectivity for CO₂ over N₂. FIG. 6 clearly showsboth factors and highlights the high loading of PPN-6-CH₂DETA andexceptional selectivity over N₂. The poor N₂ adsorption forPPN-6-CH₂DETA may be attributed to the low porosity of this compound(0.264 cm³ g⁻¹).

9. Material Regeneration Tests

To test the cyclability of PPN-6-CH₂DETA, temperature and vacuum swingswere simulated and the data was collected with an ASAP2020 analyzer. ThePPN was saturated with CO₂ at 273 K and a pressure up to 1.1 bar. Uponsaturation, the sample was kept under vacuum (0.1 mmHg) for 100 min at atemperature of 80° C. Twenty cycles (adsorption and desorption) weretested to determine whether there was any change in CO₂ uptake. Theresults are shown in FIG. 7.

FIG. 7 demonstrates that after twenty cycles, there was no apparent lossin capacity of the PPN, indicating complete desorption during eachregeneration cycle. The energy required for regeneration ofPPN-6-CH₂DETA is substantially lower than that required for aminesolutions, in which the higher chemisorption interactions (˜50-100kJ/mol) necessitate heating the solution, which contain about 70% water,to around 100° C., since the energy consumption is directly linked tothe high heat capacity of water (4.15 J g⁻¹ K⁻¹).

1. A porous polymer network comprising a moiety of Formula (A)

wherein T is —C, —Si, —Ge, —Sn, —P, —B, —N, —C₁₀H₁₆, —NO₂, —CHO, —OH,—OCH₃ or —OCH₂CH₃, R₁ to R₁₆ are each independently selected from —H,—F, —Cl, —Br, —I, —OH, —NH₂, an alkyl, CH₂Q, COQ and SO₂Q, wherein Q isa functional group, with the proviso that when at least one of R₁ to R₁₆is CH₂Q, Q is not an alkyl group, and at least one of R₁ to R₁₆ isCH₂-polyamine.
 2. The porous polymer network according to claim 1,wherein T is selected from the group consisting of —C, —Si, —Ge and—C₁₀H₁₆.
 3. The porous polymer network according to claim 1, wherein Tis —C or —Si.
 4. The porous polymer network according to claim 1,wherein the functional group is selected from an alkyl group having 1 to6 carbon atoms, an amine and a polyamine.
 5. The porous polymer networkaccording to claim 1, wherein the functional group is selected from—C₃H₇, —C₄H₉, —C₅H₁₁ and —C₆H₁₃. 6-7. (canceled)
 8. The porous polymernetwork according to claim 1, wherein the polyamine is represented byN(A₁)A₂, wherein A₁ and A₂ are each independently selected from —H, asaturated or unsaturated polyalkylamine and a saturated or unsaturatedpolyalkarylamine.
 9. The porous polymer network according to claim 1,wherein the polyamine is represented by N(A₁)A₂, wherein A₁ and A₂ areeach independently selected from —H, a branched or unbranched alkyl or abranched or unbranched alkylamine having 1 to 12 carbon atoms which isoptionally mono- or polysubstituted by —OH or —NH₂, and wherein one ormore non-adjacent —CH₂ groups is optionally replaced, in each caseindependently from another by —O—, or —N(A₃), wherein A₃ is —H, abranched or unbranched alkyl or a branched or unbranched alkylaminehaving 1 to 12 carbon atoms, with the proviso that at least one of A₁and A₂ is not hydrogen.
 10. The porous polymer network according toclaim 9, wherein N(A₁)A₂ is selected from the group consisting of:


11. The porous polymer network according to claim 10, wherein N(A₁)A₂ is


12. The porous polymer network according to claim 1, wherein theproportion of amine per gram of the porous polymer network is in therange of 1 to 1000 mmol.
 13. A method of preparing a porous polymernetwork, comprising: (a) a step of homo-coupling a monomer of formula 1

in the presence of 2,2′-bipyridyl, 1,5-cycloocta-1,5-diene, a mixedsolvent of DMF/THF and a compound or mixture selected from the groupconsisting of bis(1,5-cycloocta-1,5-diene)nickel(0), Ni(PPH₃)₄ andZn/NiCl₂/NaBr/PPH₃, at a temperature in the range of 20 to 40° C.,wherein T is —C, —Si, —Ge, —Sn, —P, —B, —N, —C₁₀H₁₆, —NO₂, —CHO, —OH,—OCH₃ or —OCH₂CH₃, R is —F, —Cl, —Br, —I, an alkenyl group or an alkynylgroup, R₁ to R₁₆ are each independently selected from —H, —F, —Cl, —Br,—I, —OH, —NH₂ and an alkyl group; and (b) a step of functionalizing theproduct obtained in step (a) with a compound selected from CH₂Q, whereinQ is a polyamine.
 14. The method according to claim 13, wherein T isselected from the group consisting of —C, —Si, —Ge and —C₁₀H₁₆.
 15. Themethod according to claim 13, wherein T is —C or —Si. 16-18. (canceled)19. The method according to claim 13, wherein the polyamine isrepresented by formula N(B₁)B₂, wherein B₁ and B₂ are each independentlyselected from —H, a saturated or unsaturated polyalkylamine and asaturated or unsaturated polyalkarylamine.
 20. The method according toclaim 13, wherein the polyamine is represented by formula N(B₁)B₂,wherein B₁, and B₂ are each independently selected from —H, a branchedor unbranched alkyl or a branched or unbranched alkylamine having 1 to12 carbon atoms which is optionally mono- or polysubstituted by —OH or—NH₂, and wherein one or more non-adjacent —CH₂ groups is optionallyreplaced, in each case independently from another by —O—, or —N(A₃),wherein A₃ is —H, a branched or unbranched alkyl or a branched orunbranched alkylamine having 1 to 12 carbon atoms, with the proviso thatat least one of B₁ and B₂ is not hydrogen.
 21. The method according toclaim 13, wherein the ratio of THF to DMF is in the range of 1:10 to10:1.
 22. (canceled)
 23. A method of storing a gas comprisingincorporating a gas into the porous polymer network according toclaim
 1. 24. The method of storing a gas according to claim 23, whereinthe gas is CH₄.
 25. A method of separating a gas from a gaseous mixture,comprising a step of contacting the gaseous mixture with a porouspolymer network according to claim 1 such that a selected gas isincorporated into the porous polymer network and is thereby separatedfrom the gaseous mixture.
 26. The method according to claim 25, whereinthe gaseous mixture comprises CO₂ and N₂.
 27. (canceled)